Electrical high-voltage energy accumulators for electrically driven motor vehicles operate at operating voltages of several 100 V and therefore represent a fire risk in particular in the case of a crash. The high-voltage energy accumulators are therefore accommodated in battery housings which have a high structural stability, on the one hand, and a high resistance to heat and fire, on the other hand. The high-voltage energy accumulators are typically installed in the vehicle floor such that the housing cover of the energy accumulator housing is assigned the important function of thermally shielding the potentially burning energy accumulator in relation to the vehicle cabin as effectively as possible and for as long as possible.
In the automotive industry there is generally the requirement of a maximum reduction in weight. Therefore, light materials, for example aluminum, magnesium, fiber-reinforced plastics, etc., are often used instead of steel. However, said light materials in relation to steel have a comparatively low melting point and are therefore suitable only to a limited extent for a battery housing or for the housing cover of a battery housing, respectively.
Automotive high-voltage energy accumulators which have a housing structure, the battery modules being disposed in the housing space of said housing structure, are known in each case from EP 2 863 470 A1 and EP 3 041 081 A1. The housing space or the housing structure, respectively, is closed by way of a separate housing cover. The housing cover is composed of a hollow metal body, one or a plurality of tiers from an insulation material being loosely placed in the cover space of said hollow metal body.